1. Field of the Invention
The present invention relates to a manufacturing method for a hollow panel. The present invention particularly relates to a manufacturing method for obtaining highly rigid, light-weight hollow panels made by layering boards made from materials such as fibers or wood element.
2. Description of Related Art
According to the recent shortage of lumber resources, more attention is recently paid on the conservation of forests, thus deforestation will be less available for future. As far as board products such as block boards manufactured from a large volume of lumber resources is concerned, unstable supplies or shortages are anticipated, as well as increases in the market price. Consequently, wood panels made by utilizing wood strands which were conventionally a waste product and ligneous fibers made from scrap wood pieces are gathering more attention; therefore, the use of wood panels in areas in which block boards were conventionally used is anxiously desired.
Regarding such wood panels, for example, wood panels shown in FIGS. 12 through 14 are already known.
The wood panel shown in FIG. 12 is made by layering, on both sides of paper honeycomb 1, flat wood boards 2 and 2 which are thinner than the paper honeycomb 1.
The wood panel shown in FIG. 13 is made by layering, on both sides of a core material 3, surface layers 4 and 4 which are thinner than the core material 3 and which are made from a uniformly molded board made of bound wood strands which are made by binding the wood strands.
The wood panel show in FIG. 14 is made in such a way that corrugated resin molded board 5 is disposed between flat wood boards 6.
The advantage of wood panels shown in FIGS. 12 through 14 is their high rigidity and lightness; however, the high manufacturing cost because of the complicated manufacturing steps is a problem in such wood panels.
An object of the present invention is to provide a more economical manufacturing method for highly rigid, light, and variously shaped hollow panels made by layering the board made from materials such as fibers or wood elements.
In the present manufacturing method for hollow panels, ribs and holes are formed by layering, with a plurality of cores, fibers and wood elements, to which binders are added, performing thermal compression molding on the layered materials, and extracting the cores after the thermal compression molding.
According to the present manufacturing method for hollow panels, the manufacturing steps are simplified by a uniform molding of medium layers and surface layers of the hollow panel. As a result, the manufacturing cost can be reduced, and the dimension of the holes in the hollow panels can be more precise. Also, a greater variety of hollow panel can be manufactured by combined use of a small number of cores. Also, the panels are light because of the hollow construction. This hollow construction helps improving heat insulating and soundproofing effects by means of the aerial layer in the holes. Also, the rigidity of the hollow panels can be enhanced by ribs formed between the holes in the hollow panel and by the walls at ends of the hollow panel. Also, according to the present manufacturing method for hollow panels, convex sections can be easily formed at a horizontal end of the hollow panel, and concave sections can be easily formed on the other horizontal end of the hollow panel for the purpose of uniting a plurality of panels. Also, according to the present manufacturing method for hollow panels, cables can be easily embedded in the ribs between holes.
In a second aspect of the manufacturing method for hollow panels, the wood elements are wood strands.
In a third aspect of the manufacturing method for hollow panels, the core is a combination of bars having irregular cross sectional shape.
In a fourth aspect of the manufacturing method for hollow panels, the core is a combination of bars of uniform cross sectional shape, or different between the bars.
In a fifth aspect of the manufacturing method for hollow panels, the cores are connected along the shorter direction of the cores by a connection board.